Add initial version of snapshot tests to bootstrap
When making any changes to bootstrap (steps), it is very difficult to realize how does it affect various common bootstrap commands, and if everything still works as we expect it to. We are far away from having actual end-to-end tests, but what we could at least do is have a way of testing what steps does bootstrap execute in dry run mode. Now, we already have something like this in `src/bootstrap/src/core/builder/tests.rs`, however that is quite limited, because it only checks executed steps for a specific impl of `Step` and it does not consider step order.
Recently, when working on what I thought was one of the simplest possible step untanglings in bootstrap (https://github.com/rust-lang/rust/pull/142357), I ran into errors in tests that were quite hard to debug. Partly also because the current staging test diffs are multiline and use `Debug` output, so it's quite difficult for me to make sense of them.
In this PR, I introduce `insta`, which allows writing snapshot tests in a very simple way. With it, I want to allow writing tests that will clearly show us what is going on during bootstrap execution, and then write golden tests for `build/check/test` stage `0/1/2` for compiler/std/tools etc., to make sure that we don't regress something, and also to help with [#t-infra/bootstrap > Proposal to cleanup stages and steps after the redesign](https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Proposal.20to.20cleanup.20stages.20and.20steps.20after.20the.20redesign/with/523488806), to help avoid a situation where we would (again) have to make a flurry of staging changes because of unexpected consequences.
In the snapshot tests, we currently render the build of rustc, std and LLVM. Currently I render the executed steps using downcasting, which is not super pretty, but it allows us to make the test rendering localized in one place, and it's IMO enough for now.
I implemented only a single test using the new machinery. Maybe if you take a look at it, you will understand why 😆 Bootstrap currently does some peculiar things, such as running a stage 0 std step (even though stage 0 std no longer exists) and running the Rustc stage 0 -> 1 step twice, once with a single crates, once with all rustc crates. So I think that even with this single step, there will be a bunch of things to fix in the near future...
The way we currently prepare the Config test fixtures is far from ideal, this is something I think ``@Shourya742`` could work on as a part of their GSoC project (remove as much command execution from Config construction as possible, actually run bootstrap on a temporary directory instead of running it on the rustc checkout, create a Builder-like API for creating the Config test fixtures).
r? ``@jieyouxu``
Assorted bootstrap cleanups (step 2)
Very small improvements designed towards making bootstrap tests less hacky/special, and towards making it possible to run bootstrap tests in parallel.
Best reviewed commit by commit.
r? ``@jieyouxu``
Add documentation for `PathBuf`'s `FromIterator` and `Extend` impls
I think it's not very obvious that `PathBuf`'s `Extend` and `FromIterator` impls work like `PathBuf::push`, so I think these should be documented.
I'm not very happy with the wording and examples, open to suggestions :)
Refactor `rustc_attr_data_structures` documentation
I was reading through `AttributeKind` and realized that attributes like `InlineAttr` didn't appear in it, however, I found them in `rustc_codegen_ssa` and understood why (guessing).
There's almost no overall documentation for this crate, I've added the organized documentation at the top of `lib.rs`, and I've grouped the Attributes into two categories: `AttributeKind` that run all through the compiler, and the ones that are only used in `codegen_ssa`, such as `InlineAttr`, `OptimizeAttr`, `InstructionSetAttr`.
Also, I've added documentation for `AttributeKind` that further explains why attributes like `InlineAttr` don't appear in it, with examples for each variant.
r? ```@jdonszelmann```
Expose discriminant values in stable_mir
Resolves https://github.com/rust-lang/project-stable-mir/issues/93
* Added `Discr` struct to stable mir as stable version of struct with same name
* Added `discriminant_for_variant` method to `AdtDef` and `CoroutineDef`
Use `LLVMIntrinsicGetDeclaration` to completely remove the hardcoded intrinsics list
Follow-up to rust-lang/rust#142259
This also needs a rustc-perf run, because `Intrinsic::getType` can be expensive
`@rustbot` label A-LLVM A-codegen T-compiler
r? `@workingjubilee`
cc `@nikic`
Rollup of 10 pull requests
Successful merges:
- rust-lang/rust#133952 (Remove wasm legacy abi)
- rust-lang/rust#134661 (Reduce precedence of expressions that have an outer attr)
- rust-lang/rust#141769 (Move metadata object generation for dylibs to the linker code )
- rust-lang/rust#141937 (Report never type lints in dependencies)
- rust-lang/rust#142347 (Async drop - fix for StorageLive/StorageDead codegen for pinned future)
- rust-lang/rust#142389 (Apply ABI attributes on return types in `rustc_codegen_cranelift`)
- rust-lang/rust#142470 (Add some missing mailmap entries)
- rust-lang/rust#142481 (Add `f16` inline asm support for LoongArch)
- rust-lang/rust#142499 (Remove check run bootstrap)
- rust-lang/rust#142543 (Suggest adding semicolon in user code rather than macro impl details)
r? `@ghost`
`@rustbot` modify labels: rollup
It currently has two, which don't accurately capture what's happening --
the `TupleStruct` spans are allocated in `ResolverArenas`, which is
different to where the `Expr` is allocated -- and require some
"outlives" constraints to be used.
This commit adds another lifetime, renames the existing ones, and
removes the "outlives" constraints.
Suggest adding semicolon in user code rather than macro impl details
This PR tries to find the right span (by peeling expansion) so that the suggestion for adding a semicolon is suggested in user code rather than in the expanded code (in the example a macro impl).
Fixesrust-lang/rust#139049
r? `@fmease`
